Cost-effectiveness and long-term effectiveness of Internet-based cognitive behaviour therapy for severe health anxiety

Background. Severe health anxiety is a common condition associated with functional disability, making it a costly disorder from a societal perspective. Internet-based cognitive behaviour therapy (ICBT) is a promising treatment but no previous study has assessed the cost-effectiveness or long-term outcome of ICBT for severe health anxiety. The aim of this study was to investigate the cost-effectiveness and 1-year treatment effects of ICBT for severe health anxiety. Method. Cost-effectiveness and 1-year follow-up data were obtained from a randomized controlled trial (RCT) comparing ICBT (n=40) to an attention control condition (CC, n=41). The primary outcome measure was the Health Anxiety Inventory (HAI). A societal perspective was taken and incremental cost-effectiveness ratios (ICERs) were calculated using bootstrap sampling. Results. The main ICER was -1244 pound, indicating the societal economic gain for each additional case of remission when administering ICBT. Baseline to 1-year follow-up effect sizes on the primary outcome measure were large (d=1.71-1.95). Conclusions. ICBT is a cost-effective treatment for severe health anxiety that can produce substantial and enduring effects. Received 23 December 2011; Revised 5 April 2012; Accepted 18 April 2012; First published online 21 May 2012